System Control Blocks

Offset
o (0) 44
44 (2C) 1
45 (20) • 6
Bytes and
Alignment
51 (33) ••• 2
53 (35) • 3
56 (38) 3
59 (3B) ••• 1
60 (3C) 1
61 (3D) • 1
62 (3E)
15 (4B)
13
82 (52) •• 2
1
FORMAT 1 -- IDENTIFIER DATA SET CONTROL BLOCK
Field Hex.
Name Dig. Field Description, Contents, Meaninq
DS1DSNAM
DS1FMTID
DS1DSSN
DS1VOLSQ
DS1CREIJI'
DS1EXPIJI'
DS1NOEPV
DS1NOBDB
DS1SYSCD
DS1DSORG
Byte 1
1 ...
. 1 •.
• • 1.
•.• 1
1 ...
• 1 ..
• • 1.
• .. 1
Data set name in EBCDIC.
Format identifier: Hex F1 identifies this as a format
1 DSCB.
Data set serial number. This field is identical to
the contents of the volume serial number field in the
volume label of the first or only volume on which the
data set resides.
Volume sequence number in binary. Indicates the
order of this volume relative to the first volume on
which the data set resides.
creation date in binary, in the form ydd.
y - year: 00 - 99
dd - day: 1 - 366
Expiration date in binary, in the form ydd (as
above). Indicates the year and the day of the year
the data set may be purged. If neither a retention
period nor an expiration date has been specified, ydd
is zero.
Number of separate extents in Which the data set
resides on this volume. This count does not include
the extent describing a user's label track.
Number of bytes used in the last PDS directory block.
A value of zero indicates that the last available
block is not being used.
Reserved.
System code. An EBCDIC code that uniquely identifies
the operating system. The first three characters are
IBM. The remaining characters are the system code
assigned to the creating system.
Reserved.
110 OS System Control Blocks (Release 21.1)
Data set organization.
IS Indexed sequential organization.
PS Physical sequential organization •
DA Direct organization •
ex BTAM or QTAM line group •
CQ QTAM direct access message queue.
MQ QTAM problem program message queue •
PO Partitioned organization •
U Unmovable - the data contains location dependent
information.